[listingReference listWithMaxResults:1000 completion:^(FIRStorageListResult * _Nonnull result, NSError * _Nullable error) {
        if(error != nil){
            NSLog(@"Error listing files");
            NSLog(@"%@", error);
        } else {
            NSArray<FIRStorageReference *> *entries = result.prefixes;
            NSArray<FIRStorageReference *> *entryItems = result.items;
            NSLog(@"List folder complete");
            NSLog(@"%@", entries);
            NSLog(@"%@", entryItems);
        }
    }];